scholarly journals Parametric identification of a functional - structural tree growth model and application to beech trees (Fagus sylvatica)

2008 ◽  
Vol 35 (10) ◽  
pp. 951 ◽  
Author(s):  
Véronique Letort ◽  
Paul-Henry Cournède ◽  
Amélie Mathieu ◽  
Philippe de Reffye ◽  
Thiéry Constant
Keyword(s):  
Fagus Sylvatica ◽  
Tree Growth ◽  
Parametric Identification ◽  
Critical Issue ◽  
Tree Architecture ◽  
Specific Description ◽  
Fagus Sylvatica L ◽  
Species Specific ◽  
Tree Growth Model ◽  
Source Sink

Functional–structural models provide detailed representations of tree growth and their application to forestry seems full of prospects. However, owing to the complexity of tree architecture, parametric identification of such models remains a critical issue. We present the GreenLab approach for modelling tree growth. It simulates tree growth plasticity in response to changes of their internal level of trophic competition, especially topological development and cambial growth. The model includes a simplified representation of tree architecture, based on a species-specific description of branching patterns. We study whether those simplifications allow enough flexibility to reproduce with the same set of parameters the growth of two observed understorey beech trees (Fagus sylvatica L.) of different ages in different environmental conditions. The parametric identification of the model is global, i.e. all parameters are estimated simultaneously, potentially providing a better description of interactions between sub-processes. As a result, the source–sink dynamics throughout tree development is retrieved. Simulated and measured trees were compared for their trunk profiles (fresh masses and dimensions of every growth units, ring diameters at different heights) and compartment masses of their order 2 branches. Possible improvements of this method by including topological criteria are discussed.

scholarly journals How Does Radial Growth of Water-Stressed Populations of European Beech (Fagus sylvatica L.) Trees Vary under Multiple Drought Events?

Forests ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 129
Author(s):  
Tamalika Chakraborty ◽  
Albert Reif ◽  
Andreas Matzarakis ◽  
Somidh Saha
Keyword(s):  
Soil Water ◽  
Fagus Sylvatica ◽  
Tree Growth ◽  
Radial Growth ◽  
Basal Area ◽  
European Beech ◽  
Canopy Openness ◽  
Fagus Sylvatica L ◽  
The Impact ◽  
Neighborhood Competition

European beech (Fagus sylvatica L.) trees are becoming vulnerable to drought, with a warming climate. Existing studies disagree on how radial growth varies in European beech in response to droughts. We aimed to find the impact of multiple droughts on beech trees’ annual radial growth at their ecological drought limit created by soil water availability in the forest. Besides, we quantified the influence of competition and canopy openness on the mean basal area growth of beech trees. We carried out this study in five near-natural temperate forests in three localities of Germany and Switzerland. We quantified available soil water storage capacity (AWC) in plots laid in the transition zone from oak to beech dominated forests. The plots were classified as ‘dry’ (AWC < 60 mL) and ‘less-dry’ (AWC > 60 mL). We performed dendroecological analyses starting from 1951 in continuous and discontinuous series to study the influence of climatic drought (i.e., precipitation-potential evapotranspiration) on the radial growth of beech trees in dry and less-dry plots. We used observed values for this analysis and did not use interpolated values from interpolated historical records in this study. We selected six drought events to study the resistance, recovery, and resilience of beech trees to drought at a discontinuous level. The radial growth was significantly higher in less-dry plots than dry plots. The increase in drought had reduced tree growth. Frequent climatic drought events resulted in more significant correlations, hence, increased the dependency of tree growth on AWC. We showed that the recovery and resilience to climatic drought were higher in trees in less-dry plots than dry plots, but it was the opposite for resistance. The resistance, recovery, and resilience of the trees were heterogeneous between the events of drought. Mean growth of beech trees (basal area increment) were negatively impacted by neighborhood competition and positively influenced by canopy openness. We emphasized that beech trees growing on soil with low AWC are at higher risk of growth decline. We concluded that changes in soil water conditions even at the microsite level could influence beech trees’ growth in their drought limit under the changing climate. Along with drought, neighborhood competition and lack of light can also reduce beech trees’ growth. This study will enrich the state of knowledge about the ongoing debate on the vulnerability of beech trees to drought in Europe.

La pousse courte, un indicateur du degré de maturation chez le hêtre (Fagus sylvatica L.)

2000 ◽  
Vol 77 (11) ◽  
pp. 1539-1550 ◽  
Author(s):  
Eric Nicolini ◽  
Bernard Chanson
Keyword(s):  
Fagus Sylvatica ◽  
Adult Stage ◽  
Morphological Characters ◽  
Juvenile Stage ◽  
The State ◽  
Tree Architecture ◽  
Vegetative Stage ◽  
Flowering Stage ◽  
Fagus Sylvatica L

In beech, no external morphological characters that allow an understanding of how an individual stem gradually and continuously evolves from a juvenile vegetative stage toward a mature flowering stage, has ever been demonstrated. The only known traits are marcescence, indicating a juvenile stage, and flowering, indicating passage to adult stage. However, in young trees growing under a forest shadow, these markers are not visible since marcescence is not expressed and the trees are too young to flower. This study was conducted to find one or more external morphological characters that indicate the state of differentiation in beech. For that purpose, a simultaneous description of tree architecture and the short, 1-year-old, foliated growth units (u.c.) of the trees was completed. Analysis showed that the morphology of short u.c.'s evolved according to their localization in the plant, the age of the plant, and the environment where in which it is developping. Analysis also revealed that this evolution was directly related to growth in height of trees, but also and above all, to the degree of complexity reached during the trees' development. Thus, evolution of short u.c.'s is a scale on which some traits expressing internal plant potentialities (marcescence, flowering) can be localized.

scholarly journals Response of Beech (Fagus sylvatica L.) Trees to Competition—New Insights from Using Fractal Analysis

2019 ◽  
Vol 11 (22) ◽  
pp. 2656 ◽  
Author(s):  
Yonten Dorji ◽  
Peter Annighöfer ◽  
Christian Ammer ◽  
Dominik Seidel
Keyword(s):  
Fagus Sylvatica ◽  
Fractal Analysis ◽  
Laser Scanning ◽  
Tree Architecture ◽  
Ecosystem Functions ◽  
Box Dimension ◽  
Individual Tree ◽  
Wide Range ◽  
Fagus Sylvatica L ◽  
Branching Architecture

Individual tree architecture and the composition of tree species play a vital role for many ecosystem functions and services provided by a forest, such as timber value, habitat diversity, and ecosystem resilience. However, knowledge is limited when it comes to understanding how tree architecture changes in response to competition. Using 3D-laser scanning data from the German Biodiversity Exploratories, we investigated the detailed three-dimensional architecture of 24 beech (Fagus sylvatica L.) trees that grew under different levels of competition pressure. We created detailed quantitative structure models (QSMs) for all study trees to describe their branching architecture. Furthermore, structural complexity and architectural self-similarity were measured using the box-dimension approach from fractal analysis. Relating these measures to the strength of competition, the trees are exposed to reveal strong responses for a wide range of tree architectural measures indicating that competition strongly changes the branching architecture of trees. The strongest response to competition (rho = −0.78) was observed for a new measure introduced here, the intercept of the regression used to determine the box-dimension. This measure was discovered as an integrating descriptor of the size of the complexity-bearing part of the tree, namely the crown, and proven to be even more sensitive to competition than the box-dimension itself. Future studies may use fractal analysis to investigate and quantify the response of tree individuals to competition.

Short-term nitrogen dynamics are impacted by defoliation and drought in Fagus sylvatica L. branches

2019 ◽  
Vol 39 (5) ◽  
pp. 792-804 ◽  
Author(s):  
Pierre-Antoine Chuste ◽  
Catherine Massonnet ◽  
Dominique Gérant ◽  
Berndt Zeller ◽  
Joseph Levillain ◽  
...  
Keyword(s):  
Fagus Sylvatica ◽  
Nitrogen Dynamics ◽  
Short Term ◽  
Fagus Sylvatica L
Sign in / Sign up

Export Citation Format

Share Document